Recently, the solid state battery has become a hot topic in the battery industry. The source is that a few days ago, the United States Fisker Automotive Corporation released a new battery technology - solid state battery, said to allow electric car users mileage increased to 500 miles About 804 km) above, the charging time only takes 1 minute .Some even point out that the solid state battery can be 'seconds' lithium battery .International auto companies in the field of solid state batteries faster and faster, this is not the first time on the solid state Battery R & D results of the news.
So far, the development of solid-state batteries to what extent? As the outside world said so superior performance? How far away from commercialization? In this regard, "China Automotive News" reporter interviewed the relevant experts learned:
Two notable features of solid-state batteries
First, the energy density of about 2.5 to 3 times the traditional lithium battery;
The second is more secure, to eliminate the risk of accidental combustion caused by broken batteries or high temperature.
Two difficulties with solid-state batteries
First, the problem of electrolyte material itself;
Second, the interface performance control and optimization issues.For now, the road to its commercialization is still a long way.
Foreign solid-state battery results frequently
Recently, a number of new trends in solid-state batteries attracted the attention of the industry.According to foreign media reports, Fisko has applied for a solid-state battery patents and is expected to achieve mass production in 2023. Fisco claims that Fisker solid-state batteries Using a three-dimensional electrode, the energy density is 2.5 times that of a conventional lithium-ion battery.
According to the Global Solid State Battery Market 2017-2021, Toyota, Matsushita, Samsung, Mitsubishi, BMW, Hyundai Motor, Hyundai Motor Co., Ltd., Hyundai Motor Co., Dyson and other companies are stepping up the layout of the solid state battery reserve R & D. France Bolloré, the United States Sakti3 and Japan Toyota represent the polymer, oxide and sulfide three solid electrolyte technology development direction.In addition, there are reports:
1. Bologna France has invested 2,900 electric vehicles equipped with 30kWh Lithium Polymer Battery (LMP) by its subsidiary Batscap;
Toyota developed all-solid-state lithium-ion batteries, energy density of 400Wh / L, Toyota researchers said that such batteries about to commercialize in 2020;
Three. Matsushita latest solid state battery energy density increased by 3 to 4 times; Honda and Hitachi Shipbuilding established institutions have developed Ah-class batteries, is expected to mass production after three years.
For research and development, some foreign companies in the field of solid-state battery research and development alone, while others choose to jointly develop.For example, Volkswagen battery in the development of solid-state batteries relatively late, but ready to develop their own. Not long ago, Toyota announced the cooperation with Panasonic to develop solid state Batteries, a few days later, BMW announced a partnership with Solid Power to develop solid-state lithium batteries, a new plant jointly established with Japan's leading GS YUASA battery company and Mitsubishi Heavy Industries, focusing on solid-state anode lithium-ion batteries.
Domestic stepping up research and development of solid-state batteries
In our country, Chinese Academy of Sciences (hereinafter referred to as 'Chinese Academy of Sciences') layout on the solid state battery relatively early, the current five R & D team made different progress.
First, Guo Yuguo, CAS Institute of Chemistry, developed a polyether-acrylate polymer solid electrolyte with a withstand voltage of 4.5 V
Xu Xiaoxiong team from Ningbo Materials Institute of Chinese Academy of Sciences developed the oxide, sulfide solid electrolyte material, ceramic sheet, all-solid battery, and tried to industrialize with Ganfeng Lithium Co. At present, the team has taken the lead in China to develop a high- 0.2Ah ~ 10Ah series of solid-state single-cell, 10Ah solid-state single-cell energy density reached 260Wh / kg, 1000 cycles capacity retention of 88%
Cui Guanglei, Qingdao Institute of Bioenergy, Chinese Academy of Sciences team developed a polypropylene carbonate, cellulose, lithium-lanthanum zirconium oxide composite solid electrolyte, developed battery energy density reached 300Wh / kg, and for the first time completed a deep sea in the Mariana Trench test
Fourth, the CAS Shanghai Institute of Silicates Guo Xiangxin team developed a polyethylene oxide, lithium lanthanum zirconium oxide composite solid electrolyte, and developed 2Ah-class solid-state lithium-ion battery
V. The CAS Institute of Physics proposed and validated the assumption of solid state in situ. The developed energy density of 10Ah soft-pack batteries reached 310-390Wh / kg and the volume energy density reached 800-890Wh / L. The battery can be operated at room temperature 90 ℃ cycle.
In addition, the well-known battery business Ningde era also into solid-state battery research and development, at present, Ningde polymer lithium metal solid-state battery cycle to reach more than 300 weeks, capacity retention rate reached 82%.
Commercialization still needs to overcome many shortcomings
Now it seems that the development of solid-state batteries in full swing in the long run, what kind of development trend will be presented? An authoritative solid-state battery experts told the "China Automotive News" reporter, the development of solid-state batteries mainly follow two routes, one polymer route ; Second is all inorganic ceramic line, all inorganic ceramic line can be divided into two directions of oxide and sulfide .At present, the two technical routes are difficult to overcome the shortcomings, but also can not be large-scale commercial use.
Ceramic route solid battery
Ceramic route Solid-state battery is the biggest problem is relatively low energy density, similar to the existing lithium-ion battery cells than lithium iron phosphate, ternary material battery energy is low, but can be a large rate of charge and discharge. Relative to the energy density Lower makes the ceramic route of the solid state battery has no economic advantages compared with the existing battery.The expert told reporters that Japan has been in the ceramic route solid state battery has been laid for more than 10 years, with leading edge.Japanese propaganda reported in 15 minutes can be filled Electricity is completely credible.
Polymer solid state battery
Polymer solid state battery higher energy density, but the charge rate is smaller.According to reports, polymer solid state battery interface between the larger resistance, full charge requires more than 5 hours.It is precisely because of the large energy density, fast charge May be dangerous. Due to large internal resistance, polymer solid-state batteries in the charging process will cause energy loss, which is an issue that can not be ignored.In addition, the most deadly problem of polymer solid-state batteries is the higher charging temperature at room temperature Lower charge rate lower, which limits the large-scale commercial applications.However, most of the research institutions and enterprises in our country are aimed at polymer solid-state batteries.
From the perspective of global solid-state battery technology development, our country is not backward, with foreign advanced technology comparable.Chinese Academy of Sciences Qingdao Bioenergy researcher Cui Guanglei told the "China Automobile News" reporter, he led the team developed solid-state battery successfully in Mariana Trench 'Qingneng -1' all deep-sea power application demonstration, making our country become Japan after the second to master the whole sea deep lithium power technology countries.
Chinese Academy of Sciences, Tsinghua University professor Ouyang Minggao not long ago also specifically talked about the development of solid-state batteries, he said:
The United States focused on the organic-inorganic composite solid state electrolyte solid-state lithium battery research and development, small companies, start-up companies mainly Japan and South Korea are using solid inorganic solid electrolyte solid-state lithium battery research and development, many companies have introduced mass production Plan.China, Japan and South Korea's situation is similar to three countries already have a great lithium-ion battery industry chain, do not want to reinvent.
Overall, the development of solid-state batteries, the electrolyte may follow the path from the liquid, semi-solid, solid-liquid mixture to the solid state development, and finally to all solid state in the negative, the transition from graphite anode to silicon carbon anode.At present, Negative transition to silicon carbon negative, the last may turn to lithium metal negative, but this line there are still technical uncertainties.
